Technical Overcooling

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Technical Overcooling


Sep 3, 2004
jarrow - tyne and wear
I think my thermostat may be stuck open - what are the implications of the engine being overcooled, will this cause any damage ? The temp gauge dont move unless stuck in traffic(it doesnt over heat as the fan kicks in if im at a stand still long enough) and then once i start moving again the gauge drops back to zero. The water level is fine and im confident i have no air locks. I must say that the car in question is not a fiat (although i do own one) but i cant seem to get an answer anywhere else ( its a corsa b). Im sure though the principles of overcooling are the same for all engines. Much appreciated
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below operating temp means the oil isnt at correct temp, thats bad for engine wear. The engine will be running richer than it should normally (which is bad). Fuel economy and performence will take a hit.

Does sound like a jammed thermo to me as well.
a whole new thermo (possibly with gasket, not sure) would be between £8-£25 depending on car. Basically a bit of bi metalllic metal and a spring with a valve on it, very simple, but if its a city car, or one that does lots of short jorneys, it will die quicker.
In a Corsa B the guage starts at 90, so if the guage only just moves then its probably not overcooling too much. Do you have hot air coming out the vents?


Yeah the gauge only slightly moves (and i mean slightly). Hot air does come out of the vents so theres no problem there - i have to say tho i think it takes longer than normal (based on other cars ive owned) to warm up tho - but that may just me being impatient. Is there anyway for sure to see if the thermostat is at fault - i know about putting it in boiling water but to remove it the cambelt and sprokets have to be removed so its no 5min job.

Thanks for the replies so far
running a car to cold would cause the car's engine to wear alot faster than normal, as your piston's etc expand to the right measurement at operating temp.